Beach chapter aside, I'm truly disappointed reading the comments and receptions regarding the villain back stories, way too many shallow opinions and almost no one here gets its point.
Do you people watch Joker and expect it to be a backstory to make you feel bad, sympathize with or to justify the villain actions ?? ABSOLUTELY NOT, that's not the point at all. This kind of Joker-like backstory is only meant to GIVE A REASON behind the villain actions, how they become who they are, and show what lead them to the twisted and irredeemable path they're on now, you are NOT supposed to understand or sympathize with them, cuz they're now bad people, but with a history, and once they break they can't go back, essentially like Joker.
Also, the backstory is very important because it prevents them from being like Dio, aka a garbage one-dimensional bad guy that only exists for the sake of being evil.